Improvement in balancing vertical-reciprocating masses



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WILLIAM F. DURFEE, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO HIM- SELF ANDJACKSON & WILEY, OF DETROIT, MICHIGAN,

Letters Patent No. 112,792, dated una 21, 1871.

' The Schedule referred to in these Letters Patent nd making part of thesame.

To all whom fit ma/y concern:

Be it known that I, WILLIAM F.' DURFEE, of Bridgeport, in the county of'Fairfield and State of Connecticut, have invented a new and usefulImprovement in System of Balancing Vertical-reciprocating Masses; and Ido hereby declare that the following is a'full, clear, and exactdescription thereof, whichv will enable others skilled in the art tomake and use the same, reference being had to the accompanying dre-wingforming part of this specification.

The drawing represents a vertical centralf'section of a verticalsteam-engine, showing my improvement ap plied.

My inventionrelates to and consists in a new way of balancing thepistons of vertical steam-engines,- pump-rodsin' mines, the top roll 0frolling-mills, the saws of saw-mills, and other vertically-reciprocatingmasses. Y l

The principle of my invention consists in balancing the weight of avertically-movable mass of matter by a piston connected therewith, andreceiving a continu ous supply of steam at boiler-pressure uponits-lower side, the said steam raising the movable weight on the upwardstroke, and offering an equal amount of e resistance thereto on thedownward stroke.

l will now describe a vertically-working piston, as illustrative of andfully exemplitying my new idea or plan.'

G in the drawing represents' the main cylinder of an uprightsteam-engine:

P, the piston; and

R, the piston-rod.

R is the upper-part of the piston-rod, having the same cross-sectionalarea as the part Rv;

P', au auxiliary piston;

C', the chamber, in which the latter travels; and

T, a pipe, connecting with the steam-boiler.

B is a stufiing-box, between the two piston-cylinders C G, to preventsteam from passing from one to the other along the piston-rod.v

The mode of operation is as follows:

The cylinder C (through the pipe T) receives steam at boiler-pressure,which acts upon the under surface of the piston P. This under surface isso proportioned in its area that the forceof steam is exactly (or enoughso for all practical' purposes) equal to `the weight of thereciprocating mass; thus, on the upward stroke it entirely lifts thismass, and on the downward stroke altagonizes it, offering'a resistanceequal to the gravity thereof'. In this manner the weight of all themoving parts is completely neutralized, while on the down stroke thesteam is also returned, without waste, to the boiler.`

Having thus described all that isnecessary to a full understanding of myinvention,

What I esteem to be new, and desire to secure by Letters Patent, is-

A piston, P', and cylinder C, combined, as described,

with a pipe, T, receiving steam at boiler-pressure, for the purpose ofneutralizing vertically-movable masses of mattei', as described.

Witnesses.: WILLIAM F. DUEFEE.

M. DIAMOND, R. P. CHAPMAN.

